Hi John,

Thanks a lot for your detail instruction. We will try with the external
biased microphone.

Regards,
Dustin

On Wed, Dec 3, 2014 at 11:37 PM, John Syn <[email protected]> wrote:

>
> From: Dien Nguyen <[email protected]>
> Reply-To: "[email protected]" <[email protected]>
> Date: Tuesday, December 2, 2014 at 6:35 PM
> To: "[email protected]" <[email protected]>
> Subject: Re: [beagleboard] Audio capture issue with BeagleBone Black and
> Audio Cape Rev B
>
> Hi John,
>
> Have you tried to record with external microphone?
>
> You have to bias the microphone, but the audio cape didn't implement the
> microphone bias circuitry so you will have to bias the microphone
> externally for it to work. If you search for the TLV320AIC3106EVM
> schematic, you can see how to bias the microphone.
>
>
> The recording works fine if I connect the Audio Cape directly to the
> speaker source (a tablet) with a male-to-male 3.5mm cable. In case of using
> external microphone, the Audacity Frequency Analysis shows there is no
> frequency that is higher than 3KHz.
> I tried the same test with USB Sound Card and it works fine.
>
> I haven't checked the audio bandwidth, but if I use a sampling rate of
> 96KHz, the audio quality sounds fine.
>
>
> Do you have some special setting for alsamixer?
>
> The only settings I change is Press F4 for Capture, make "Line Line2
> Bypass" = 100 and "PGA" = 50
>
> Here is the command I use:
>
> arecord -c1 -f S32_LE -r 96000 -t wav -vv test.wav
> or
> aplay -C -c1 -f S32_LE -r 96000 -t wav -vv test.wav
>
> I use the second command because my debugger gets confused when loading
> alsa-util debug symbols. After all, arecord is just a soft link to aplay.
>
> Regards,
> John
>
>
> Thanks,
> Dustin
>
> On Tuesday, December 2, 2014 4:10:12 AM UTC+7, john3909 wrote:
>>
>>
>> On 12/1/14, 10:27 AM, "Nicolae Rosia" <[email protected]> wrote:
>>
>> >Hello,
>> >
>> >The clock is wrong. For some reason the clock clock rate is not
>> >changed to 12MHz as set in dts file but to 24MHz (ti,codec-clock-rate
>> >= <12000000>;).
>> >If you change the clock to 24MHz in your dts, it will work as expected.
>> I¹m not sure that is how this is supposed to work. Surely the DTS defines
>> the clock rate rather than reflecting the clock rate? My guess is that
>> the
>> ALSA subsystem is reading the DTS codec-clock-rate, but the MCASP_AHCLKX
>> isn¹t been set correctly by the MCASP code and simply defaulting to
>> 24MHz.
>>
>> Regards,
>> John
>> >
>> >Regards,
>> >Nicolae Rosia.
>> >
>> >On Mon, Dec 1, 2014 at 4:42 PM, Dien Nguyen
>> ><[email protected]> wrote:
>> >> Hi Jesse,
>> >>
>> >> Tried out with 48KHz, same issue occurred. Have you recorded and
>> played
>> >> successfully with any kernel version?
>> >>
>> >> Thanks,
>> >> Dustin
>> >>
>> >> On Mon, Dec 1, 2014 at 2:05 PM, Jesse Cobra <[email protected]>
>> >>wrote:
>> >>>
>> >>> Curious what happens if you try 48k sampling?
>> >>>
>> >>> On Nov 30, 2014 9:37 PM, "Dien Nguyen" <[email protected]>
>> >>> wrote:
>> >>>>
>> >>>> Hi John,
>> >>>>
>> >>>> Did you solve the issue yet, may you please share how to fix it? We
>> >>>>also
>> >>>> tried with 3.18 and the issue is still there.
>> >>>>
>> >>>> Thanks,
>> >>>> Dustin
>> >>>>
>> >>>> On Mon, Dec 1, 2014 at 12:29 PM, John Syn <[email protected]>
>> wrote:
>> >>>>>
>> >>>>>
>> >>>>> From: Dien Nguyen <[email protected]>
>> >>>>> Reply-To: "[email protected]"
>> >>>>><[email protected]>
>> >>>>> Date: Sunday, November 30, 2014 at 7:14 PM
>> >>>>> To: "[email protected]" <[email protected]>
>> >>>>> Subject: [beagleboard] Audio capture issue with BeagleBone Black
>> and
>> >>>>> Audio Cape Rev B
>> >>>>>
>> >>>>>
>> >>>>> Hi All,
>> >>>>>
>> >>>>> We tried the Audio Cape Rev B with BeagleBone Black. The kernel
>> >>>>>version
>> >>>>> is 3.14.17 (https://github.com/RobertCNelson/bb-kernel.git branch
>> >>>>> am33x-v3.14)
>> >>>>>
>> >>>>> We was able to play and record via the Audio Cape. If we record and
>> >>>>>play
>> >>>>> the file via the Audio Cape, it works fine. But when we move the
>> >>>>>recorded
>> >>>>> file to other machine or play it via the USB Sound Card, the speed
>> >>>>>of the
>> >>>>> recorded file seems 1.5 time slower than it really is.
>> >>>>>
>> >>>>> On the board, we recorded the audio with
>> >>>>> arecord -t raw -f S16_LE -r 44100 /tmp/1.raw
>> >>>>>
>> >>>>> Then, we playback the file with command
>> >>>>> aplay -t raw -f S16_LE -r 44100 /tmp/1.raw
>> >>>>>
>> >>>>> 1/ On x86 machine, the voice become very slow. If we change the
>> >>>>>sampling
>> >>>>> rate to 63000, it is played close to the real voice we recorded.
>> >>>>> 2/ Trying with a USB Sound Card plugged directly to the board.
>> >>>>> aplay -t raw -f S16_LE -r 44100 -D plughw:1,0 /tmp/1.raw
>> >>>>> We saw the same issue as seen on x86 machine
>> >>>>>
>> >>>>> It seems that there is something wrong with the sampling rate
>> clock.
>> >>>>>May
>> >>>>> anyone please give some suggestions
>> >>>>>
>> >>>>> I¹ve seen the same problem when recording on the BBB and then
>> playing
>> >>>>> the same file on my Ubuntu Desktop. Not sure why this happens. I¹m
>> >>>>>using
>> >>>>> 3.15.10-bone8.
>> >>>>>
>> >>>>> Regards,
>> >>>>> John
>> >>>>>
>> >>>>>
>> >>>>> Thanks
>> >>>>>
>> >>>>> --
>> >>>>> For more options, visit http://beagleboard.org/discuss
>> >>>>> ---
>> >>>>> You received this message because you are subscribed to the Google
>> >>>>> Groups "BeagleBoard" group.
>> >>>>> To unsubscribe from this group and stop receiving emails from it,
>> >>>>>send
>> >>>>> an email to [email protected].
>> >>>>> For more options, visit https://groups.google.com/d/optout.
>> >>>>>
>> >>>>> --
>> >>>>> For more options, visit http://beagleboard.org/discuss
>> >>>>> ---
>> >>>>> You received this message because you are subscribed to a topic in
>> >>>>>the
>> >>>>> Google Groups "BeagleBoard" group.
>> >>>>> To unsubscribe from this topic, visit
>> >>>>>
>> >>>>>https://groups.google.com/d/topic/beagleboard/
>> XmMg5DjJvsk/unsubscribe.
>> >>>>> To unsubscribe from this group and all its topics, send an email to
>> >>>>> [email protected].
>> >>>>> For more options, visit https://groups.google.com/d/optout.
>> >>>>
>> >>>>
>> >>>> --
>> >>>> For more options, visit http://beagleboard.org/discuss
>> >>>> ---
>> >>>> You received this message because you are subscribed to the Google
>> >>>>Groups
>> >>>> "BeagleBoard" group.
>> >>>> To unsubscribe from this group and stop receiving emails from it,
>> >>>>send an
>> >>>> email to [email protected].
>> >>>> For more options, visit https://groups.google.com/d/optout.
>> >>>
>> >>> --
>> >>> For more options, visit http://beagleboard.org/discuss
>> >>> ---
>> >>> You received this message because you are subscribed to a topic in
>> the
>> >>> Google Groups "BeagleBoard" group.
>> >>> To unsubscribe from this topic, visit
>> >>> https://groups.google.com/d/topic/beagleboard/XmMg5DjJvsk/unsubscribe.
>>
>> >>> To unsubscribe from this group and all its topics, send an email to
>> >>> [email protected].
>> >>> For more options, visit https://groups.google.com/d/optout.
>> >>
>> >>
>> >> --
>> >> For more options, visit http://beagleboard.org/discuss
>> >> ---
>> >> You received this message because you are subscribed to the Google
>> >>Groups
>> >> "BeagleBoard" group.
>> >> To unsubscribe from this group and stop receiving emails from it, send
>> >>an
>> >> email to [email protected].
>> >> For more options, visit https://groups.google.com/d/optout.
>> >
>> >--
>> >For more options, visit http://beagleboard.org/discuss
>> >---
>> >You received this message because you are subscribed to the Google
>> Groups
>> >"BeagleBoard" group.
>> >To unsubscribe from this group and stop receiving emails from it, send
>> an
>> >email to [email protected].
>> >For more options, visit https://groups.google.com/d/optout.
>>
>>
>> --
> For more options, visit http://beagleboard.org/discuss
> ---
> You received this message because you are subscribed to the Google Groups
> "BeagleBoard" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> For more options, visit https://groups.google.com/d/optout.
>
>  --
> For more options, visit http://beagleboard.org/discuss
> ---
> You received this message because you are subscribed to a topic in the
> Google Groups "BeagleBoard" group.
> To unsubscribe from this topic, visit
> https://groups.google.com/d/topic/beagleboard/XmMg5DjJvsk/unsubscribe.
> To unsubscribe from this group and all its topics, send an email to
> [email protected].
> For more options, visit https://groups.google.com/d/optout.
>

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to